Grup de Caracterització de Materials, Departament de Física i Enginyeria Nuclear, ETSEIB, Barcelona 08028, Catalonia, Spain.
J Pharm Sci. 2012 Mar;101(3):1073-8. doi: 10.1002/jps.22821. Epub 2011 Nov 18.
The active pharmaceutical ingredient racemic benfluorex hydrochloride (benfluorex-HCl) has an interesting phase behavior due to an elusive solid-solid phase transition. The stability hierarchy between different phases is often determined based on heat-related experiments only or slurry interconversion. It is shown that if pressure and volume are taken into account, not only the phase equilibria are correctly positioned in the pressure-temperature phase diagram, but the experimental data also improves. Thus, it has been found that the racemic benfluorex-HCl is enantiotropic under "ordinary conditions" with polymorph II and polymorph I, respectively, being the low- and the high-temperature phases. Above ∼ 151 MPa, the system becomes monotropic and polymorph II is the single stable phase.
活性药物成分外消旋苯氟雷司盐酸盐（苯氟雷司盐酸盐）由于难以捉摸的固-固相变而具有有趣的相行为。不同相之间的稳定性顺序通常仅基于与热相关的实验或浆料转化来确定。结果表明，如果考虑压力和体积，则不仅可以正确地将相平衡定位在压力-温度相图中，而且还可以改善实验数据。因此，已经发现外消旋苯氟雷司盐酸盐在“普通条件”下是反型的，分别为多晶型 II 和多晶型 I，它们分别是低温相和高温相。在约 151 MPa 以上，该系统成为单型，多晶型 II 是唯一稳定的相。
